Mastech MS2225A Operation Manual page 30

1) Turn the change-over switch to the kW or W gear, first
long-press the FUNC key to enter the voltage
measurement interface, and then short-press the
FUNC key to enter the harmonics measurement
interface, and switch from 1st - 20th harmonic through
pressing the Hz/%INRUSH/▲ key or LINK/REL/▼ key.
2) Input the measured voltage signal from the V end and
COM end.
3) After the measuring circuits are connected correctly,
the effective value of the nth harmonic component shall
be read.
4) Short-press the FUNC key in the harmonic
measurement interface once again to enter into THD-R
(relative to the actual effective value) or THD-F (relative
to the fundamental wave) measurement mode. The
main interface displays the effective value of the nth
harmonic component and the minor interface displays
the total harmonic distortion.
5) Press MAX/MIN key in the voltage measurement
interface to enter the maximum/minimum value
measurement mode. In this case, the main interface
displays the measured effective value of voltage and
the minor interface displays the maximum and minimum
values within a certain period. Press the
Hz/%INRUSH/▲ key or LINK/REL/▼ key again in this
interface to enter into the time recording interface. In
this case, the main interface displays the limited voltage
measurements, and the minor interface displays the
time of maximum and minimum values.
Note:
1) The minimum measured voltage is 1 V and the
maximum measured voltage is 750 V. This interface will
display OL for over 750 V.
54
Electric shock.
Pay special attention to high current measurement to
avoid electric shock.
Do not input the current with the effective value greater
than AC 1000 A.
Figure 14 Schematic Diagram for Harmonics Measurement of

















Voltage Signal at KW Gear
WARNING
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